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This year I took the plunge and decided to try and start some plants from seed. With the help of my 4 year old I planted some seeds in pots with seed starting mix and a bit of vermiculite. I purchased a 4 ft shop light and some T8 daylight (6500K) bulbs to use for the plants. I have my seed pots in a plastic bin to keep the humidity up until they sprout. I'm growing tomatoes, peppers, basil, and squash.

How hot do the T8 fluorescent lights get? Will I be able to place the light directly over the plastic bin or could that possibly melt the plastic?

I am also in negotiations with my better (and much prettier) half about where this big light and seedlings are going to be placed. I was thinking about putting them in the garage but our temps are getting pretty low at night; 40's and 30's in the next week. This is not something we usually have to worry about in Houston during February. Is that too cold for the seedlings at night? I plan on using a reflective windshield sun block as backing on the shelf in the garage and I thought about wrapping the other sides with thick clear plastic to make a sort of shelf size "green house" of sorts.

Would it be okay to run the lights during the night (providing some heat) and turn them off during the day? The plants would be sitting in the dark garage during the day so they get to rest and have a somewhat natural cycle. As the temps warm up I would slowly change their flipped day night schedule back to our natural nay night cycle but would this cause any harm to the plants?

Hi H_TX_2! Last year I found myself in almost the same exact situation, with cold garage and everything. The T8 lights do not get hot. Remember that many (most) seeds do not need light for germination, so there would be no need for light while the plastic dome is on. And you're going to remove the dome soon as the sprouts come up. Using a heat mat (or other source of heat) underneath the tray will warm the soil mix to aid germination. As far as the day/night cycle, I would def recommend running the lights (14-18hrs) during the day so you won't have to worry about switching their cycle when it's time to put them outside.For me, this is one of the most fulfilling things about starting the garden. I love the hands-on attention and getting to see "life sprouting before me." "Praising God" emoticon

Hey H_TX! We live in Houston also, actually in Katy, and I will be getting some seeds started this weekend myself. I hadn't really thought about a light though. I was just going to put them in those 36 or 72 seed starting kits sold by Burpee. We picked one up at Tractor Supply last week. I initially intended to just set it up by a window until the seedlings got big enough to put outside.Keep us posted on how your setup goes.

Thanks mapspringer. I have my pots in a rectangular plastic tub with a lid. When I start using the light this weekend the lid will come off and the light will then be placed very close to the top edge of the plastic tub until the seedlings grow enough to raise the light. I was just worried about getting the light too close to the top edge of the plastic box.

This is my first time starting seeds indoors. There is so much to learn and understand that it almost seems overwhelming at first. I just decided to go for it and if nothing else make this year more of a learning experience. If I need to purchase plants from the nursery like I did last year then so be it. But next year I should do better than I did this year.

I know it got down in the 40's in our garage last year when I had tomatoes, peppers, etc. growing, and they survived. I did blow a ceramic space heater in there direction when I got concerned for a while, but everything grew strong when it warmed up. It won't be this cold forever!

@H_TX_2 wrote:...This is my first time starting seeds indoors. There is so much to learn and understand that it almost seems overwhelming at first. I just decided to go for it and if nothing else make this year more of a learning experience. ...

That's a good approach. I got frustrated my first two years starting seeds indoors because I tried to do too much all at once. It took me a couple years to figure out a system that worked for me, that took into account my climate, planting schedule, size of lights on hand, and available indoor space and temperature.

@H_TX_2 wrote:...I thought the plants needed a break from light and heat. If it gets down to the 30's but the plants are in my garage will the heat mat be okay to use all night long?...

When I use heat mats, they are on 24 hours a day. I've never had the MM temp get above 65°, and that was when the tray was under lights and the ambient temp and humidity were unusually high. Even cool plants thrive in that temp day and night. Don't worry about consistent heat; your warm plants will love it.

Giving plants a break from light is frequently mentioned. But I've been coming across examples where that doesn't apply.

Thanks to everyone for the info. You not only helped my plants but my marriage as well.

You should have seen my wife's face when I pulled out the 4 ft light fixture and then she asked me where I was going to put it. Knowing I can keep it in the garage where it is now will allow everything to run a little smoother.

I used newspaper pots to plant my seeds in and I planted the seeds almost 3 weeks ago. I see some are getting their true leaves so from what I have read it is about time to add some light fertilizer. Does anyone have any recommendations?

I used newspaper pots to plant the seeds in and I have been wondering if these pots will air prune the roots. This morning as I was watering the seedlings I noticed a couple had roots poking through the paper pot. So are these roots being air pruned? How long can the seedlings stay in these paper pots?

@H_TX_2 wrote:I used newspaper pots to plant my seeds in and I planted the seeds almost 3 weeks ago. I see some are getting their true leaves so from what I have read it is about time to add some light fertilizer. Does anyone have any recommendations?

I used newspaper pots to plant the seeds in and I have been wondering if these pots will air prune the roots. This morning as I was watering the seedlings I noticed a couple had roots poking through the paper pot. So are these roots being air pruned? How long can the seedlings stay in these paper pots?

Newspaper pots do Not air prune. To air prune you need an air barrier to keep the roots from crossing the open space.

I've never tried newspaper pots but I understand the whole thing can be potted up because the newspaper will disintegrate. I'd expect you would have to get the pot very wet to start the disintegration process.

@quiltbea wrote:Newspaper pots do Not air prune. To air prune you need an air barrier to keep the roots from crossing the open space.

I've never tried newspaper pots but I understand the whole thing can be potted up because the newspaper will disintegrate. I'd expect you would have to get the pot very wet to start the disintegration process.

This is what I was thinking also but since there are roots sticking out from the sides I would think that root tip will dry out and create more rooting behind it. Isn't this in simple terms what air root pruning is? The roots are poking right through the side of the paper pot. This is a good thing because I would imagine it will be easy for the roots to get through the paper once they are planted and surrounded by MM and watered well. This is my first year starting seeds and first year using the paper pots. I was wondering if I should cut slits in the paper as I put them into the ground or tear off as much as I can but since the roots are already getting through the paper I'm not worried about them being able to get out after they are planted.

You could cut slits in the paper, but really that is unnecessary as the paper becomes so fragile by itself, once the roots get bigger they will just push through it. I recommend not trying to pull paper off, you will break the fragile roots. Just pot it up in a bigger pot and you're good to go for a few more weeks.

I noticed that one of my squash seedlings has what looks like little female blooms. The flowers are not open yet. The small fruit and what will become the flower are all still very small and green right now. Is this a bad thing that the plant already trying to bloom?

It's practicing! Both the male and female flowers have to be open before fertilization can occur Unfertilized female fruits will just fall off. Don't worry at this point. You can leave it or remove it carefully.